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\begin{document}
\begin{equation*}
\begin{bmatrix}
 -26 & -3 & -6 &  2 &  2 & -1 & 0 & 0 \\
   0 & -3 & -4 &  1 &  1 &  0 & 0 & 0 \\
  -3 &  1 &  5 & -1 & -1 &  0 & 0 & 0 \\
  -4 &  1 &  2 & -1 &  0 &  0 & 0 & 0 \\
   1 &  0 &  0 &  0 &  0 &  0 & 0 & 0 \\
   0 &  0 &  0 &  0 &  0 &  0 & 0 & 0 \\
   0 &  0 &  0 &  0 &  0 &  0 & 0 & 0 \\
   0 &  0 &  0 &  0 &  0 &  0 & 0 & 0
\end{bmatrix}
\end{equation*}
\end{document}
